Tubular structure and modular building assembly using the same

ABSTRACT

This invention relates to an elongated hollow non-deformable structure that can be used as beams and pillars of modular building structures. The structure includes first and second elongated C-shaped channels ( 20 ) with inwardly bent lips ( 25 ) and means for holding the two channels ( 20 ) together so that the lips ( 25 ) kiss each other. The fust and second C-shaped channels ( 20 ) may be formed without lips ( 25 ). L-shaped ( 42 ) and T-shaped ( 40 ) and H-shaped flanges of appropriate design are provided with holes in the flanges at predetermined locations to correspond to the holes in the end portions of the beams and pillars. There are plug-able holes ( 21 ) provided in the end portions of the beams and pillars so that workers can easily access inside the hollow space to use nuts ( 72 ), washers, and bolts ( 70 ) to couple the elongated hollow structures together. Instead of the C-shaped chanel ( 20 ) structure two identical L-shaped channels ( 20   b ) may be used.

TECHNICAL FIELD

[0001] The present invention relates to a tubular structure (which generally denotes a pillar structure or a beam structure), and a building assembly including hollow tubular structures, wherein a plurality of the structures are adopted for use as beams and as pillars selectively, and more particularly, to a tubular structure in which first and second channels each having a predetermined shape are aligned to oppose each other and engaged with each other, and a building assembly of pillar and beam structures assembled on a concrete foundation.

BACKGROUND ART

[0002] In the case of a current architectural structure under construction using pillar and beam structures, a frame member forming pillars become light-weight. As a result, the architectural structure has an increased space utilization degree, an excellent heat isolation ability and a strong wet-prevention performance, to thus provide a comfortable housing environment. However, a connection structure of the existing pillar and beam structures has a complicated construction process. That is, respective connection portions require welding works which lack an assembly workability. Also, it is not so easy to maintain a heat isolation processing at the connection portion. As a result, it is much difficult to prevent a dewdrop formation and maintain a refractory performance.

[0003] For example, in case of a house made of a conventional steel frame structure, a wide flange “a” is used as a pillar structure as shown in FIG. 16. A welding process “c” is performed in order to connect the wide flange “a” with a beam “b” and then the welded flange and beam structure is transported from the welding place to a construction site. In this case, since the structure itself is large in size, it is difficult to transport it, it may be damaged during transportation, and a partially difficult welding work may be required during construction on site, which causes a difficult construction. Further, it costs much to purchase pillar and beam structures and assembly components thereof.

[0004] Also, in the case of a connection structure of pillar and beam structures as well as existing pillar and beam structures, a wide flange abutting an external structure is continuously linked with an internal structure. Accordingly, in order to prevent a dewdrop formation phenomenon, all portions abutting the external structure should be wrapped with a heat isolation material. Such an increase of the above-described partial supplementation causes construction of a structure forming a steel frame to be expansive, to thereby make an expansive architectural building, and the external appearance of the structure is also too unshaped, which thus does not represent a light and nimble steel structure architecture.

DISCLOSURE OF THE INVENTION

[0005] To solve the above problems, it is an object of the present invention to provide a tubular structure which can be applied to a pillar or a beam obtained by assembling a plurality of channels each of a predetermined section without requiring a welding work in order to solve problems in assembling structures in a conventional architectural building.

[0006] It is another object of the present invention to provide a tubular structure where a channel of a type forming lips in which each edge in a C-shaped section is bent inwards (hereinafter referred to as a C-shaped channel with inwardly bent lips), a C-shaped channel of a C-shaped section (hereinafter referred to as a C-shaped channel), or an L-shaped channel of an L-shaped section (hereinafter referred to as an L-shaped channel) is selectively applied.

[0007] It is still another object of the present invention to provide a connection structure necessary for connecting a pillar and a pillar, a pillar and a beam, or a beam and a beam, in addition to a supply of a pillar and beam structure.

[0008] It is yet another object of the present invention to provide a connection piece necessary for a connection structure in addition to a supply of the connection structure.

[0009] It is a further object of the present invention to provide a building assembly made of a pair of channels to improve a heat isolation performance.

[0010] To accomplish the above object of the present invention, there is provided a tubular structure comprising: a first elongated C-shaped channel with lips along the length thereof; a second elongated C-shaped channel with lips along the length thereof of the same design as the first rigid elongated C-shaped channel; and means for holding the two channels together so that the lips of the first C-shaped channel kiss the lips of the second C-shaped channel, wherein the lips of the first and the second C-shaped channels are respectively inwardly bent and the surfaces of the lips coming in contact with each other are planar and form airtight seal along the length thereof, whereby a hollow elongated tubular structure is formed.

[0011] Preferably, the first and the second channels are made of rigid material so that the tubular structure is substantially non-deformable.

[0012] Preferably, the first and second channels are made of steel.

[0013] Preferably, the means for holding the first and the second C-shaped channels together comprises bolting means having a bolt with a head, threaded stem and a nut, detent means to maintain the spatial distance between the opposing inside faces of the two C-shaped channels a predetermined distance as the bolt is placed and the nut is rotated to couple and tighten the two C-shaped channels together.

[0014] There is also provided a building assembly comprising hollow tubular structures, wherein a plurality of the structures are adopted for use as beams and as pillars selectively, means for anchoring the bottom ends of selected ones of the pillars on a support foundation for a building and means for coupling a second pillar on top of the first pillar end to end, and means for coupling the beams to the pillars, for building a framework of a modular building.

[0015] Preferably, the anchoring means comprises a flange of a predetermined design with a plurality of holes at predetermined positions, an end of the hollow tubular structures used as pillars provided with a plurality of holes at predetermined positions for alignment with the holes in the flange, and a plurality of nuts, washers and bolts for bolting the one end of the pillar to the flange and the other end of the flange to the foundation.

[0016] Preferably, the building assembly comprises anchoring means for the pillar including an L-shaped flange, with the “_” portion provided with holes for receiving threaded rod of bolts, the heads of which are embedded in a solid foundation for the building, the “I” portion having holes to align with holes provided through the sides of the bottom end of the pillar, nuts, bolt and washer means for bolting the end portion of the pillar to the “I” portion of the flange and for bolting the “_” portion of the flange to the foundation, for anchoring the pillar to the building foundation.

[0017] Preferably, the coupling means includes an H-shaped type flange of a size such that it fits inside the hollow space of the pillars and being positioned so that one thereof being fitted inside the top end portion of the first pillar, the other end thereof being fitted inside the bottom end of a second pillar, the H-shaped flange and the end portions of the first and second pillars are provided with a plurality of holes at predetermined positions, nuts, bolts and washer means for bolting the first and the second pillars to the H-shaped flange through the poles. (FIG. 10)

[0018] Preferably, the H-shaped flange is positioned to provide continuity of empty space between the two pillars, whereby utility lines such as water pipe, communications or power supply cable lines can be run through the hollow spaces provided by the first and the second hollow tubular pillars, the H-shaped flange and the top end portion of first pillar and the bottom end portion of the second pillars are provided with holes at predetermined positions.

[0019] Preferably, the coupling means includes T-shaped flanges designed to fit inside the hollow space of the beam made of the pillar structure, wherein the T-shaped flanges and an end portion of the beam are provided with a plurality of holes at predetermined positions, nut, bolt and washer means for fastening the T-shaped flange to the H-shaped flange and to the beam through the plurality of holes provided therein for mounting the beam transverse to the pillar.

[0020] Preferably, the lips of the beam toward the end thereof are eliminated to accommodate the T-flange being inserted into the hollow beam.

[0021] Preferably, the assembly comprises a pair of T-shaped flanges, each with a plurality of holes in its flanges at predetermined positions, the pair of flanges dimensioned and positioned so that their “_” portions are in parallel and the flanges meeting the inner surface at the end portion of the C-shaped channel, and nuts, washers and bolt means for bolting together the beam end to the H-shaped member that couples two pillars. (FIG. 10)

[0022] Preferably, the beams and the pillars are provided with plug-able access holes adjacent the holes in the ends of the tubular means used as pillars and as beams for facilitating the access into the inner hollow space of the pillars and beams for facilitating the bolting operations for mounting the bolts and nuts and washers, to couple and tighten pillars to the building foundation, pillars to pillars, and beams to pillars, for facilitating the assembly of a building.

[0023] Preferably, an insulating means is inserted between the T-shaped flanges and the end portions of the two pillars such that the hollow space inside of the two pillars is insulated from the exterior.

[0024] There is also provided a non-deformable elongated hollow structure useable as a pillar or as a beam, comprising a pair of substantially identical C-shaped channel, and means for mating and coupling the pair of the C-shaped channels into each other to form an hollow rectangular elongated structure.

[0025] There is also provided an assembly comprising a plurality of the hollow elongated structure, wherein the structures are adopted to be the pillars and the beams of a modular building assembly structure, mean comprised of flanges and nuts and bolts and washers and a plurality of holes provided in the flanges and in the end portions of the tubular structures used as the beams and as the pillars, plug-able holes provided in the pillars and beams for facilitating the use of wrenches and pliers to couple the pillars and the beams into each other and to the foundation through the flanges to build a framework for an building.

[0026] Preferably, the assembly includes means for reinforcing the way the two C-shaped channels are brought together by bolting the two channels with bolt, nut, washer means and a retainer for maintaining the space between the inner opposite walls as the nut is rotated to tighten the bolt against nut to hold the two opposing C-shaped channels.

[0027] Preferably, to enforce the coupling strength the lip joint of the C-shaped channels meeting each other is spot-welded.

[0028] There is also provided a non-deformable elongated hollow structure useable as a pillar or as a beam, comprising a pair of substantially identical L-shaped channel, means for mating and coupling the pair of the L-shaped channels into each other to form an hollow rectangular elongated structure.

[0029] There is also provided an assembly comprising a plurality of the hollow elongated structure wherein the structures are adopted to be the pillars and the beams of a modular building assembly structure, mean comprised of flanges and nuts and bolts and washers and a plurality of holes provided in the flanges and in the end portions of the tubular structures used as the beams and as the pillars, plug-able holes provided in the pillars and beams for facilitating the use of wrenches and pliers to couple the pillars and the beams into each other and to the foundation through the flanges to build a framework for an building.

[0030] Preferably, the assembly includes means for reinforcing the way the two L-shaped channels are brought together by bolting the two channels with bolt, nut, washer means and a retainer for maintaining the space between the inner opposite walls as the nut is rotated to tighten the bolt against nut to hold the two opposing L-shaped channels.

[0031] Preferably, to enforce the coupling strength the lip joint of the L-shaped channels meeting each other is spot-welded.

[0032] There is also provided a connection structure for connecting tubular structures which are assembled with first and second channels each having the same section which butt each other, and a connection unit for connecting the first and second channels, the connection structure comprising: a wide flange for reinforcing a connection force necessary for connecting the vertically extended first and second channels, which is positioned in the first and second channels and is provided with several connection holes thereon; connection pieces provided with connection holes for connecting a pillar structure and a pillar structure, a pillar structure and a beam structure, and a beam structure and a beam structure; and connection units for connecting the pillar structure, the wide flange, the beam structure and the connection pieces.

[0033] Preferably, the connection piece is of a T shape, or an L shape.

[0034] Preferably, the first and second channels are provided with working access holes for facilitating an engagement of the wide flange at predetermined positions in which the working access hole is closed with a closure.

[0035] Preferably, the connection structure further comprises a reinforcing plate on which connection holes are formed in order to reinstate a height of the inserted portion of the wide flange at the time of engaging the connection pieces.

[0036] Preferably, in the case of the connection structure of the pillar and beam structures, a pair of C-shaped channels with inwardly bent lips, C-shaped channels without inwardly bent lips or L-shaped channels are connected to form a pillar or a beam by using bolts for fixing the wide flange and the channels, and a heat isolation material is filled between the C-shaped channel with inwardly bent lips, C-shaped channel or L-shaped channel and the wide flange where an external portion meets an internal portion, to thereby prevent a dewdrop formation.

[0037] Preferably, in the case of the connection structure of the tubular structures, ducts for water supply and drainage, electric power cable and telecommunication cable pass through the internal path of the structures, to thereby provide a variety of architectural space.

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The above objects and other advantages of the present invention will become more apparent by describing the preferred embodiment thereof in more detail with reference to the accompanying drawings in which:

[0039]FIG. 1 is a perspective view of a tubular structure according to a first embodiment of the present invention in which channels have been assembled;

[0040]FIG. 2 is a perspective view of the tubular structure according to the first embodiment of the present invention in which channels have been disassembled;

[0041]FIG. 3A is a sectional view of FIG. 1 cut along line A-A, which shows the tubular structure according to the first embodiment of the present invention in which channels have been assembled;

[0042]FIG. 3B is a sectional view of FIG. 1 cut along line B-B, which shows the tubular structure according to the first embodiment of the present invention in which channels have been assembled;

[0043]FIG. 4 is a perspective view of another example of a channel which can be employed in the tubular structure according to the first embodiment of the present invention;

[0044]FIG. 5A is a perspective view of a tubular structure according to a second embodiment of the present invention in which channels have been assembled;

[0045]FIG. 5B is a perspective view of a channel disassembled from the structure according to the second embodiment of the present invention;

[0046]FIG. 5C is a perspective view of another example of a channel which can be employed in the structure according to the second embodiment of the present invention;

[0047]FIG. 6A is a perspective view of a tubular structure according to a third embodiment of the present invention in which channels have been assembled;

[0048]FIG. 6B is a perspective view of a channel disassembled from the tubular structure according to the third embodiment of the present invention;

[0049]FIG. 7 is a perspective view showing an example of a tubular structure in which structures according to the present invention are connected;

[0050]FIG. 8 is an enlarged, exploded, and perspective view of portion “A” of. FIG. 7, in which a pillar structure according to the present invention is connected and fixed to a concrete foundation;

[0051]FIGS. 9A, 9B and 9C are sectional views of FIG. 7 cut along line C-C, in which FIG. 9A shows a connection structure of a pillar structure according to the present invention in which a first example of a channel has been applied, FIG. 9B shows a connection structure of a pillar structure according to the present invention in which a second example of a channel has been applied, and FIG. 9C shows a connection structure of a pillar structure according to the present invention in which a third example of a channel has been applied;

[0052]FIG. 10 is an enlarged, exploded, and perspective view of portion “B” of FIG. 7, which shows a connection structure of a pillar and a pillar, and a pillar and a beam according to the present invention;

[0053]FIG. 11 is a perspective view showing a connection structure of a pillar and a pillar according to the present invention;

[0054]FIG. 12A is an exploded perspective view showing a beam structure according to the present invention in which channels of the first example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention;

[0055]FIG. 12B is an exploded perspective view showing a beam structure according to the present invention in which channels of the second example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention;

[0056]FIG. 12C is an exploded perspective view showing a beam structure according to the present invention in which channels of the third example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention;

[0057]FIG. 13A is a perspective view showing a connection piece of a T-shaped section which is applied to a connection of a pillar and beam structure according to the present invention;

[0058]FIG. 13B is a perspective view showing a connection piece of an L-shaped section which is applied to a connection of a pillar and beam structure according to the present invention;

[0059]FIG. 14 is a perspective view showing a connection structure of a beam and a beam according to the present invention;

[0060]FIG. 15 is a sectional view showing an example of a layout where ducts for water supply and drainage, telecommunication and power cables, etc., pass through the inside of the pillar structure or beam structure according to the present invention; and

[0061]FIG. 16 is a perspective view showing a conventional pillar structure and a connection state where a beam is connected to the pillar structure.

BEST MODE FOR CARRYING OUT THE INVENTION

[0062] Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0063] Referring to FIGS. 1 through 3B, a tubular structure according to a first embodiment of the present invention is made of two channels, that is, first and second channels 20 each having a C-shaped section with inwardly bent lips, in which the first and second channels 20 are opposed to each other and assembled with each other. In each of the first and second channels 20, connection holes 22 are formed on the wide surfaces, lips 25 which are bent inwards are formed at the edges of the opening sides on the narrow surfaces, and the lips 25 are removed from the edges of the opening sides on the narrow surfaces only at the portions where the connection holes 22 are formed.

[0064] Also, the half a working access hole 21 is perforated on each of the narrow surfaces of the first and second channels 20. After assembly, a closure 50 is fitted in each of the working access holes 21 or unfitted therefrom.

[0065] Connection holes 23 are perforated at the intermediate portion on each of the wide surfaces in the tubular structure. The connection holes 23 are fitted with a long bolt 71 and are engaged with a nut 73, to thereby support the intermediate portions of the first and second channels 20. A tubular straw 76 which is fitted into the long bolt 71 is provided inwards from the first and second channels 20.

[0066] As shown in FIGS. 3A and 3B, the tubular structure according to the first embodiment of the present invention is used as a pillar structure or a beam structure since a predetermined rectangular section is formed at the state where the first and second channels 20 are assembled.

[0067]FIG. 4 is a perspective view of another example of a channel 20 which can be employed in the tubular structure according to the first embodiment of the present invention, in which connection holes 22 are formed on narrow surfaces of the channels, and working access holes 21 are formed on wide surfaces thereof.

[0068] Referring to FIG. 4, the assembled structure of the channels 20 are opposed to the tubular structure according to the first embodiment of the present invention, as shown in FIGS. 1 through 3B, in which the wide surfaces and the narrow surfaces of FIG. 4 play the opposite roles to those of the first embodiment.

[0069]FIG. 5A is a perspective view of a tubular structure according to a second embodiment of the present invention in which channels have been assembled, and FIG. 5B is a perspective view of a channel disassembled from the tubular structure according to the second embodiment of the present invention.

[0070] Referring to FIGS. 5A and 5B, the tubular structure according to the second embodiment of the present invention is provided with the first and second channels 20 a in which the lips 25 of the first embodiment has been removed from the inner bent portions, differently from the channels 20 of the first embodiment.

[0071] In the tubular structure according to the second embodiment of the present invention as shown in FIGS. 5A and 5B, the channels each having the C-shaped section which are the first and second channels 20 a each having the same section are aligned to face each other and assembled with each other. In each of the first and second channels 20 a, the connection holes 22 are formed on the wide surface in which the narrow surface is formed inwards from the channel.

[0072] Also, the half a working access hole 21 is formed on each of the narrow surfaces of the first and second channels 20 a. After assembly, a closure 50 is fitted therein and unfitted therefrom.

[0073] The connection holes 23 are perforated in the intermediate portions of the tubular structure and fitted with a long bolt 71 and are engaged with a nut 73, to thereby support the intermediate portions of the first and second channels 20 a.

[0074] Like the first embodiment of the present invention, a straw 76 fitted with a long bolt 71 is provided in the inside of the first and second channels 20 a. As a result, the pillar structure and the beam structure of the second embodiment of the present invention form a section of a predetermined rectangular shape at the state where the first and second channels 20 a each having a C-shaped section are abutted to each other and assembled with each other.

[0075]FIG. 5C is a perspective view of another example of a channel which can be employed in the tubular structure according to the second embodiment of the present invention, in which the installation positions of connection holes 22 and the working access holes 21 are altered from the first embodiment of the present invention. That is, the connection holes 22 are formed on the narrow surfaces being the opening edges of the first and second channels 20 a and the working access holes 21 are formed on the wide surfaces thereof.

[0076]FIG. 6A is a perspective view of a tubular structure according to a third embodiment of the present invention in which channels have been assembled, and FIG. 6B is a perspective view of a channel disassembled from the structure according to the third embodiment of the present invention.

[0077] Referring to FIGS. 6A and 6B, channels 20 b applied in the tubular structure according to the third embodiment of the present invention each have an L-shaped section and are opposed to each other and assembled with each other.

[0078] Since the working access holes 21, the connection holes 22 and 23, the closure 50 and the reinforcement unit in the third embodiment are provided like the first and second embodiments, the detailed description thereof will be omitted.

[0079]FIG. 7 is a perspective view showing part of the whole tubular structure illustrating examples of connection structures of the pillar and pillar and beam and beam according to the present invention.

[0080] Referring to FIG. 7, the lower portion of the pillar structure according to the present invention is a portion “A” which is vertically fixed on a concrete foundation 10. Also, the beam structure is a portion “B” which is extended from the lateral portion of the pillar structure. That is, the pillar structure is vertically fixed on the concrete foundation 10, and the beam structures are extended from the appropriate portion of the pillar structure according to the present invention.

[0081]FIG. 8 is an enlarged, exploded, and perspective view of portion “A” of FIG. 7, in which a pillar structure according to the present invention is connected and fixed to a concrete foundation.

[0082] As shown in FIG. 8, the pillar structure is assembled on the concrete foundation 10. The concrete foundation 10 is a heavy-weight product of a substantially rectangular shape, in which relatively long fixing holes 12 are formed in the four comers on the concrete foundation 10. Anchor bolts 74 are threadedly fitted into the fixing holes 12.

[0083] When a pillar structure is installed on the concrete foundation 10, support plates 26 are preferably installed on the lower side of each of the channels 20, 20 a, or 20 b. For example, a support plate 26 is welded and integrated on the lower side of each of the first and second channels 20, in which connection holes 24 are formed in correspondence to the fixing holes 12. The support plate can be applied to the channels of all the embodiments of the present invention if the shape in the lower portion of the support plate is designed to meet those of the other channels.

[0084] Referring to FIG. 8, the pillar structure formed of the first and second channels 20 each having a C-shaped section with inwardly bent lips are vertically installed on the concrete foundation.

[0085] The connection holes 24 are formed on the support plate 26, each of which is fitted with an anchor bolt 74 to accomplish a vertical fixture of the pillar structure.

[0086] A wide flange 30 of a predetermined length is fitted between the channels forming the pillar structure. Connection holes 32 are also formed on the wide flange 30, which are engaged during connection of the channels 20, 20 a, or 20 b.

[0087] Although the pillar structure is installed on the concrete foundation 10 in FIG. 8, it is possible to connect a pillar structure with a pillar structure, which will be described in detail with reference to FIG. 11 illustrating a connection structure.

[0088]FIGS. 9A, 9B and 9C are sectional views of FIG. 7 cut along line C-C, in which FIG. 9A shows a connection structure of a pillar structure according to the present invention in which a first example of a channel has been applied, FIG. 9B shows a connection structure of a pillar structure according to the present invention in which a second example of a channel has been applied, and FIG. 9C shows a connection structure of a pillar structure according to the present invention in which a third example of a channel has been applied.

[0089] The first example of the channel 20 in the-first embodiment of the present invention has a C-shaped section with inwardly bent lips. As shown in FIG. 9A, each of the channels 20 has a wide surface and a narrow surface which is bent inwards from each of the upper and lower portions of the wide surface. Bent lips 25 are formed inwards from the narrow surfaces.

[0090] In the case of the pillar structure assembled with the channels 20, the wide flange 30 is positioned inwards between the wide surfaces, which is engaged by bolts 70 and nuts 72. Although they are not shown in FIG. 9A, working access holes 21 may be formed on the narrow surface, on which a closure 50 is fitted as shown in FIGS. 2 and 3A. Also, a heat isolation material 80 can be inserted between the channels and the internal wide flange 30, to thereby prevent a dewdrop formation.

[0091] The second example of the channel 20 a in the second embodiment of the present invention has a C-shaped section. As shown in FIG. 9B, each of the channels 20 a has a wide surface and a narrow surface which is bent inwards from each of the upper and lower portions of the wide surface. In the case of the pillar structure assembled with the channels 20 a, the wide flange 30 is positioned inwards between the wide surfaces, which is engaged by bolts 70 and nuts 72. Although they are not shown in FIG. 9B, working access holes 21 may be formed on the narrow surface, on which a closure 50 is fitted as shown in FIGS. 2 and 3A. Also, a heat isolation material 80 can be inserted between the channels and the internal wide flange 30, to thereby prevent a dewdrop formation.

[0092] The third example of the channel 20 b in the third embodiment of the present invention has an L-shaped section. As shown in FIG. 9C, each of the channels 20 b has two surfaces each having the same width which are perpendicular to each other. In the case of the pillar structure assembled with the channels 20 b, two channels 20 b are aligned to oppose each other and engaged with bolts 70 and nuts 72. Here, a wide flange 30 is positioned inwards between the wide surfaces, which is engaged by the bolts 70 and the nuts 72. Although they are not shown in FIG. 9C, working access holes 21 may be formed on the narrow surface, on which a closure 50 is fitted as shown in FIGS. 2 and 3A. Also, a heat isolation material 80 can be inserted between the channels and the internal wide flange 30, to thereby prevent a dewdrop formation.

[0093] The reason why the heat isolation material 80 is disposed between the channels 20, 20 a or 20 b and the wide flange 30 is to prevent a dewdrop formation due to a temperature difference between the internal and external portions.

[0094]FIG. 10 is an enlarged, exploded, and perspective view of portion “B” of FIG. 7, which shows a connection structure of a pillar and a pillar, and a pillar and a beam according to the present invention. FIG. 11 is a perspective view showing a connection state of a pillar and a pillar according to the present invention. The pillar and pillar structure according to the present invention as shown in FIGS. 10 and 11 is simple.

[0095] That is, as shown in FIG. 11, a wide flange 30 is vertically installed inwards from the space formed of the channels 20, 20 a or 20 b between the lower pillar structure and the upper pillar structure, and then the lower and upper ends of the upper pillar structure and the lower pillar structure are abutted and engaged with bolts 70 and nuts .72. In the case of FIG. 10, since beam structures are also connected together with the pillar structures, the upper and lower pillar structures are assembled at the state where the beam structures are spaced by a predetermined distance from the pillar structures, during fixing of the beam structures.

[0096]FIG. 12A is an exploded perspective view .showing a beam structure according to the present invention in which channels of the first example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention. FIG. 12B is an exploded perspective view showing a beam structure according to the present invention in which channels of the second example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention. FIG 12C is an exploded perspective view showing a beam structure according to the present invention in which channels of the third example have been applied, and a connection structure of the beam structure with respect to a pillar structure according to the present invention. FIG. 13A is a perspective view showing a connection piece of a T-shaped section which is applied to a connection of a pillar and beam structure according to the present invention. FIG. 13B is a perspective view showing a connection piece of an L-shaped section which is applied to a connection of a pillar and beam structure according to the present invention.

[0097] The connection structure of the tubular structure will be described with reference to FIGS. 12A through 13B together with FIG. 10.

[0098] The connection structure between the vertically extended pillar structures according to the present invention uses a T-shaped connection piece 40 or an L-shaped connection piece 42 on which connection holes 44 are formed as shown in FIGS. 13A and 13B. Besides, the above-described wide flange 30, bolts 70, nuts 72 and a thickness adjustment plate 60 on which connection holes 62 are formed are used for the connection structure.

[0099] First, the wide flange 30 is disposed between the lower pillar structure and the upper pillar structure which are vertically installed with respect to each other. Two connection pieces 40 each having a T-shaped section are fixedly connected on the wide flange 30 which is exposed between the pillar structures with an appropriate interval according to the space interval of the beam structure.

[0100] Then, the beam structure obtained by assembling a pair of channels 20, 20 a or 20 b which are abutted with each other, are horizontally abutted on a corresponding position of the wide flange 30 having a predetermined interval vertically.

[0101] That is, as shown in FIG. 12A, two channels 20 of the first example according to the present invention are abutted and engaged with a long bolt 71 and a nut 73, to thereby form a beam structure. The assembled beam structure is fitted into connection holes 44 on the connection pieces 40 each having a T-shaped section which are opposed and fixed to each other, to then be engaged with bolts 70 and nuts 72. Here, part of the lips 25 on the channels 20 each having a C-shaped section with inwardly bent lips is removed in order to prevent a contact to the connection pieces 40.

[0102] The channels 20 a of the second example which is used in the second embodiment of the present invention as shown in FIG. 12B, and the channels 20 b of the third example which is used in the third embodiment of the present invention as shown in FIG. 12C, are assembled into a beam structure in the same manner as that of the first embodiment of the present invention. Then, The assembled beam structure is fitted into connection holes 44 on the connection pieces 40 each having a T-shaped section which are opposed and fixed to each other, to thereby complete a connection structure of the beam structure with the channels 20 a and 20 b of the second and third examples which are used in the second and third embodiments of the present invention.

[0103]FIG. 14 is a perspective view showing a connection structure of a beam and a beam according to the present invention.

[0104] In the case of a beam structure according to the present invention, various types of beam structures can be prepared by using the channels 20, 20 a and 20 b of the first through third examples according to the first through third embodiments of the present invention.

[0105] In the case that a beam structure has been prepared, two upper and lower connection pieces 42 each having an L-shaped section are fixed on predetermined positions of the beam structure, and then the prepared beam structure is fitted and engaged with the previously assembled beam structure, to thereby accomplish a connection between a beam structure and a beam structure.

[0106]FIG. 15 is a sectional view showing an example of a layout where ducts for water supply and drainage, telecommunication and power cables, etc., pass through the inside of the pillar structure or beam structure according to the present invention. As shown in FIG. 15, in the case of the structure according to the present invention, ducts for water supply and drainage, telecommunication and power cables, etc., can be installed through the structure after completing a predetermined building.

[0107] As described above, the present invention provides a tubular structure such as a pillar structure or a beam structure by using channels and connection members each having a predetermined shape, without exerting welding works. Also, the structures can be assembled on site without pre-assembling the structures to carry them to the working site. Further, an assembly is simplified to reduce an installation cost and an excellent construction efficiency is enhanced to shorten a construction period, to accordingly enable a small number of persons to install and construct the structures. Also, a dewdrop formation can be prevented at a connection portion. An assembled product becomes light-weight to thereby provide an easy transportation. A path formed in the structure can be used as those of the ducts for water supply and drainage, telecommunication and power cables, etc. 

What is claimed is:
 1. A tubular structure comprising: a first elongated C-shaped channel with lips along the length thereof, a second elongated C-shaped channel with lips along the length thereof of the same design as said first rigid elongated C-shaped channel, and means for holding the two channels together so that the lips of said first C-shaped channel kiss the lips of said second C-shaped channel, wherein the lips of said first and said second C-shaped channels are respectively inwardly bent and the surfaces of the lips coming in contact with each other are planar and form airtight seal along the length thereof. whereby a hollow elongated tubular structure is formed.
 2. A tubular structure according to claim 1, wherein said first and said second channels are made of rigid material so that the tubular structure is substantially non-deformable.
 3. A tubular structure according to claim 1 or 2, wherein said channels are made of steel.
 4. A tubular structure according to claim 2 or 3, wherein said means for holding said first and said second C-shaped channels together comprises bolting means having a bolt with a head, threaded stem and a nut, detent means to maintain the spatial distance between the opposing inside faces of the two C-shaped channels a predetermined distance as the bolt is placed and the nut is rotated to couple and tighten said two C-shaped channels together.
 5. A building assembly comprising hollow tubular structures according to any one of claims 1 to 4, wherein a plurality of said structures are adopted for use as beams and as pillars selectively, means for anchoring the bottom ends of selected ones of said pillars on a support foundation for a building and means for coupling a second pillar on top of said first pillar end to end, and means for coupling said beams to said pillars, for building a framework of a modular building.
 6. A building assembly according to claim 5, wherein said anchoring means comprises a flange of a predetermined design with a plurality of holes at predetermined positions, an end of the hollow tubular structures used as pillars provided with a plurality of holes at predetermined positions for alignment with the holes in the flange, and a plurality of nuts, washers and bolts for bolting the one end of the pillar to the flange and the other end of the flange to the foundation.
 7. An assembly according to claim 6, including said anchoring means for the pillar including an L-shaped flange, with the “_” portion provided with holes for receiving threaded rod of bolts, the heads of which are embedded in a solid foundation for the building, the “I” portion having holes to align with holes provided through the sides of the bottom end of the pillar, nuts, bolt and washer means for bolting the end portion of the pillar to the “I” portion of the flange and for bolting the “_” portion of the flange to the foundation, for anchoring the pillar to the building foundation.
 8. An Assembly according to claim 5, wherein the coupling means includes an H-shaped type flange of a size such that it fits inside the hollow space of the pillars and being positioned so that one thereof being fitted inside the top end portion of the first pillar, the other end thereof being fitted inside the bottom end of a second pillar, said H-shaped flange and the end portions of said first and second pillars are provided with a plurality of holes at predetermined positions, nuts, bolts and washer means for bolting the first and the second pillars to the H-shaped flange through the poles.
 9. An Assembly according to claim 8, wherein said H-shaped flange is positioned to provide continuity of empty space between the two pillars, whereby utility lines such as water pipe, communications or power supply cable lines can be run through the hollow spaces provided by the first and the second hollow tubular pillars, said H-shaped flange and said top end portion of first pillar and the bottom end portion of the second pillars are provided with holes at predetermined positions,
 10. An Assembly according to claim 8, wherein said coupling means includes T-shaped flanges designed to fit inside the hollow space of the beam made of the pillar structure, wherein said T-shaped flanges and an end portion of the beam are provided with a plurality of holes at predetermined positions, nut, bolt and washer means for fastening the T-shaped flange to the H-shaped flange and to the beam through the plurality of holes provided therein for mounting the beam transverse to the pillar.
 11. An assembly according to claim 10, wherein the lips of the beam toward the end thereof are eliminated to accommodate the T-shaped flange being inserted into the hollow beam.
 12. An assembly according to claim 8, comprising a pair of T flanges, each with a plurality of holes in its flanges at predetermined positions, said pair of flanges dimensioned and positioned so that their “_” portions are in parallel and the flanges meeting the inner surface at the end portion of the C-shaped channel, and. nuts, washers and bolt means for bolting together the beam end to the H-shaped member that couples two pillars.
 13. An assembly according to claim 12, wherein said beams and said pillars are provided with plug-able access holes adjacent the holes in the ends of the tubular means used as pillars and as beams for facilitating the access into the inner hollow space of the pillars and beams for facilitating the bolting operations for mounting the bolts and nuts and washers, to couple and tighten pillars to the building foundation, pillars to pillars, and beams to pillars, for facilitating the assembly of a building.
 14. An assembly according to claim 13, wherein an insulating means is inserted between the T flanges and the end portions of the two pillars such that the hollow space inside of the two pillars is insulated from the exterior.
 15. A non-deformable elongated hollow structure useable as a pillar or as a beam, comprising a pair of substantially identical C-shaped channel, and means for mating and coupling the pair of the C-shaped channels into each other to form an hollow rectangular elongated structure.
 16. An assembly comprising a plurality of the hollow elongated structure according to claim 15, wherein said structures are adopted to be the pillars and the beams of a modular building assembly structure, mean comprised of flanges and nuts and bolts and washers and a plurality of holes provided in the flanges and in the end portions of the tubular structures used as the beams and as the pillars, plug-able holes provided in the pillars and beams for facilitating the use of wrenches and pliers to couple the pillars and the beams into each other and to the foundation through the flanges to build a framework for an building.
 17. An assembly according to claim 16, including means for reinforcing the way the two C-shaped channels are brought together by bolting the two channels with bolt, nut, washer means and a retainer for maintaining the space between the inner opposite walls as the nut is rotated to tighten the bolt against nut to hold the two opposing C-shaped channels.
 18. An assembly structure according to claim 17, wherein to enforce the coupling strength the lip joint of the C-shaped channels meeting each other is spot-welded.
 19. A non-deformable elongated hollow structure useable as a pillar or as a beam, comprising a pair of substantially identical L shaped channel, and means for mating and coupling the pair of the L-shaped channels into each other to form an hollow rectangular elongated structure.
 20. An assembly comprising a plurality of the hollow elongated structure according to claim 19, wherein said structures are adopted to be the pillars and the beams of a modular building assembly structure, mean comprised of flanges and nuts and bolts and washers and a plurality of holes provided in the flanges and in the end portions of the tubular structures used as the beams and as the pillars, plug-able holes provided in the pillars and beams for facilitating the use of wrenches and pliers to couple the pillars and the beams into each other and to the foundation through the flanges to build a framework for an building.
 21. An assembly according to claim 20, including means for reinforcing the way the two L-shaped channels are brought together by bolting the two channels with bolt, nut, washer means and a retainer for maintaining the space between the inner opposite walls as the nut is rotated to tighten the bolt against nut to hold the two opposing L-shaped channels.
 22. An assembly structure according to claim 21, wherein to enforce the coupling strength the lip joint of the L-shaped channels meeting each other is spot-welded. 